Microsoft Defender isn't bad, but it's not enough to fully protect your PC. You don't have to pay extra, though—just use one of the top free antivirus apps we've tested.

A new program from eMed and the NIH offers free tests and treatments, and you don't even need to leave your home.

Virus removal tools can be standalone one-time scanners or built into full antivirus software. They scan your system for malicious files and remove them. Standalone tools are great as a second opinion ...